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Generalized ordered Bell numbers Bo(5,n).
23

%I #36 Jan 15 2024 00:50:57

%S 1,5,55,905,19855,544505,17919055,687978905,30187495855,1490155456505,

%T 81732269223055,4931150091426905,324557348772511855,

%U 23141780973332248505,1776997406800302687055,146197529083891406394905

%N Generalized ordered Bell numbers Bo(5,n).

%C Fifth row of array A094416, which has more information.

%H Vincenzo Librandi, <a href="/A094418/b094418.txt">Table of n, a(n) for n = 0..200</a>

%H Paul Barry, <a href="https://arxiv.org/abs/1803.06408">Three Études on a sequence transformation pipeline</a>, arXiv:1803.06408 [math.CO], 2018.

%F E.g.f.: 1/(6 - 5*exp(x)).

%F a(n) = Sum_{k=0..n} A131689(n,k)*5^k. - _Philippe Deléham_, Nov 03 2008

%F a(n) ~ n! / (6*(log(6/5))^(n+1)). - _Vaclav Kotesovec_, Mar 14 2014

%F a(0) = 1; a(n) = 5 * Sum_{k=1..n} binomial(n,k) * a(n-k). - _Ilya Gutkovskiy_, Jan 17 2020

%F a(0) = 1; a(n) = 5*a(n-1) - 6*Sum_{k=1..n-1} (-1)^k * binomial(n-1,k) * a(n-k). - _Seiichi Manyama_, Nov 16 2023

%t t = 30; Range[0, t]! CoefficientList[Series[1/(6 - 5 Exp[x]), {x, 0, t}], x] (* _Vincenzo Librandi_, Mar 16 2014 *)

%o (Magma)

%o A094416:= func< n,k | (&+[Factorial(j)*n^j*StirlingSecond(k,j): j in [0..k]]) >;

%o A094418:= func< k | A094416(5,k) >;

%o [A094418(n): n in [0..30]]; // _G. C. Greubel_, Jan 12 2024

%o (SageMath)

%o def A094416(n,k): return sum(factorial(j)*n^j*stirling_number2(k,j) for j in range(k+1)) # array

%o def A094418(k): return A094416(5,k)

%o [A094418(n) for n in range(31)] # _G. C. Greubel_, Jan 12 2024

%o (PARI) my(N=25,x='x+O('x^N)); Vec(serlaplace(1/(6 - 5*exp(x)))) \\ _Joerg Arndt_, Jan 15 2024

%Y Cf. A094416, A094417, A094419, A094422, A131689.

%Y Cf. A346984, A365568, A365569, A365570.

%K nonn

%O 0,2

%A _Ralf Stephan_, May 02 2004